SciRPUS. 



CYPERACEiE. 



355 



regarded as a distinct species. The European -S. maritimus (of which my specimens are 

 not good), seems to embrace the same two forms as ours. 



9. Scirpus atroviuens, Muhl. Dark Green Clubrush. 



Culm triangular, leafy ; umbel compound, proliferous ; involucre about 3-leaved ; spikes 

 ovoid, acute, glomerated in dense heads of 15 to 20 ; scales ovate, mucronate, pubescent; 

 bristles as long as the achenium ; style 3-cleft ; achenium obovoid, compressed-triangular, 

 tapering towards the base, acuminate, dull. — Muhl. gram. p. 43 ; Torr. ft. 1. p. 49, and 

 Cyp. p. 325 ; Beck, hot. p. 426 ; Darlingt. ft. Cest. p. 22 ; Kunth, enum. 2. p. 170. S. 

 polyphyllus, Valil, enum. 2. p. 274? ; Pursh, ft. 1. p. 57 (excl. syn.). 



Culm obtusely triangular, about two feet high, leafy nearly to the summit, smooth. Leaves 

 about one-fourth of an inch wide, mostly shorter than the culms, rough on the margin. Umbel 

 very unequal ; one or more of the rays elongated and erect. Spikes many-flowered, 2-3 

 lines long. Scales broadly ovale, keeled, abruptly acuminate and mucronate, at first olive- 

 green and somewhat pubescent, but, when old, fuscous and nearly smooth. Bristles 6, slender, 

 hispid downward, sometimes one or two of them a little longer than the achenium. Stamens 

 3. Style moderately 3-cleft. Achenium whitish, sharply acuminate, flat, the inside very 

 convex, and obtusely angular externally. 



Wet meadows and swamps : common. FL July. Fr. August. 



10. Scirpus brunneus, Muhh Brown-headed Clubrush. 



Culm triangular, leafy ; umbel decompound ; involucre 3 - 4-leaved ; spikes short-ovoid 

 and ovoid-oblong, somewhat loosely clustered in heads of 5 to 8 ; scales broadly ovate, rather 

 obtuse, slightly mucronate ; style 3-cleft ; achenium minute, obovate, plano-convex, with a 

 short acumination, dull, shorter than the somewhat crisped bristles. — Muhl. gram. p. 43 ; 

 Torr. ft. 1. p. 49, and Cyp. p. 326 ; Beck, hot. p. 426 ; Darlingt. ft. Cest. p. 22. S. ex- 

 altatus, Pursh, fl. 1. p. 56 ; Ell. sk. 1. p. 87. S. polyphyllus, Kunth, enum. 2. p. 170; 

 also of Vahl ? 



Stem 2-4 feet high, obtusely triangular below, acutely triangular above. Leaves broad, 

 as tall as the umbel ; the principal rays about 5, two to three inches or more in length. Spikes 

 commonly rather longer than in the preceding species. Scales keeled, mostly of a brownish 

 color ; when old, slightly acute and mucronate. Bristles 6, slender, pubescent downwards, 

 nearly twice as long as the achenium. Stamens 3. Achenium whitish, acuminate with a very 

 short point, flat behind, convex or very obtusely angular in front. 



Swamps and borders of ponds, usually in shady places : rare. Fl. July. Fr. August. 

 Although this species can, in general, be readily distinguished, there sometimes occur what 

 seem to be intermediate forms. S. atrovirens is known bv its dark green foliage and spikes, 

 more simple umbel, and one or two of the rays elongated and nearly erect, as well as by its 

 denser heads of spikes. In S. brunneus, the umbel is larger, the spikes brownish, fewer in 

 a head and less closely aggregated. 



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